The Sampling Core serves as the most important resource for the Center Grant. It is through the operation of this Core that the HLA-typed blood donors who fall into the age range specified, and who donate blood on a regular basis, are identified and flagged so that the buffy coats can be obtained. The PBMC that are generated from the buddy coats are then distributed to the various projects, technical components or pilot projects that may require them. The second source of samples from this Core is bronchial alveolar lavage (BAL) cells that will be obtained from compensated donors. Our collaborators, Drs. Elizabeth Jacobs and Randolph Lipchik, at the Medical College of Wisconsin, will obtain the BAL. The Core will be responsible for a generation of a sample database, for sample distribution and archiving unused portions of the samples for possible later studies. The Core will perform some routine analyses on the samples that include surface marker analysis and measurement of influenza antibody titers. The Core is under the direction of Dr. Jack Gorski.